Line current differential (87L) protection schemes face extra challenges compared with other forms of differential protection, in addition to the traditional requirements of sensitivity, speed, and immunity to current transformer saturation. Some of these challenges include data communication, alignment, and security; line charging current; and limited communications bandwidth. To address these...

In this paper, a novel pulsed power generator based on IGBT stacks is proposed for wide pulsed power applications. Because it can generate high voltage pulsed output without any step-up transformer or pulse forming network, it has advantages of fast rising time, easiness of pulse width variation, high repetition rate and rectangular pulse shapes. Proposed scheme consists of multiple power stage...

Transformers are one of the more expensive pieces of equipment found in a distribution network. The transformer’s role has not changed over the last decades. With simple construction and at the same time mechanically robust, they offer long term service that on average can reach half a century. Today, with the ongoing trend to supply a growing number of non-linear loads along with the notion of...

Power transformers with superconducting windings need a protection system to prevent damage to the low-loss superconducting winding by an abnormally high current. The generally accepted protection technique which uses auxiliary coils has been analysed using a network representation. The current distribution between main and auxiliary coil is expressed in terms of geometrical parameters. Experim...

With the rapid development of wind energy, relay protection for large-scale wind farms has been attracting some researchers, due to the absence of standards. Based on the large-scale doubly fed induction generator (DFIG)-based wind farms located in Gansu Province, China, this paper studies the differential protection for the outgoing power transformer of large-scale DFIG-based wind farms. Accor...

Abstract: Nowadays, the use of distributed generation (DG) has increased because of benefits such as increased reliability, reduced losses, improvement in the line capacity, and less environmental pollution. The protection of microgrids, which consist of generation sources, is one of the most crucial concerns of basic distribution operators. One of the key issues in this field is the protection...

Demand response (DR) enables customers to adjust their electricity usage to balance supply and demand. Although commercial and industrial DR have been in use for decades, residential DR is still emerging. The goal of this paper is to design a DR scheme for residential customers. We consider households operating various appliances and propose a distributed DR scheme to manage the appliances to k...

When defining a scheme of a web application, modelers repeatedly perform modelling tasks like “after having defined an entity type, add a page class for displaying the entity type’s content”. Thereby, a scheme is extended again and again in a similar manner. For such recurrent tasks, it would be convenient for modelers to have web scheme transformers (short transformers) that, when applied to a...

Toroidal transformers are used to measure the beam current in beam lines and accelerators. Placing such a transformer hi the feedback loop of an operational amplifier will increase the useful frequency range (active current transformer). A magnetic modulator can be added to extend the response to DC current, maintaining with a control loop the transformer core at a zero flux state. The magnetic...